Insulative materials and layers of insulative materials are used extensively in various semiconductor applications to insulate or electrically isolate structural features and circuit elements. The insulative properties of such materials and layers can often be affected by the ability to minimize or exclude void areas formed during the deposition of the insulative material. Uniformity of deposition rates across a deposited layer during deposition can influence film quality and ability to effectively minimize void inclusion. As feature size of devices decreases, widths of gaps to be filled also decreases and aspect ratio of such gaps can become very high. Accordingly, minimization of void area within gap-fill becomes more difficult but increasingly important for effective isolation. The variance in deposition rate across a surface can make optimizing deposition conditions and parameters for void exclusion difficult if not impossible.
One method that has been utilized to address the need for precision gap-fill is high density plasma chemical vapor deposition (HDP-CVD). Further improvements over other conventional methods have been conferred by replacing sputtering gases such as argon conventionally utilized in HDP-CVD systems, with an alternative sputtering gas such as H2. The replacement with H2 has allowed reduced occurrence of voids in gap-fill applications under certain deposition conditions.
It is desirable to develop improved gap-fill techniques and methods for providing improved deposition rate uniformity.